The Collaborative International Dictionary of English v.0.48:

Flounce \Flounce\, n.
   The act of floucing; a sudden, jerking motion of the body.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Flounce \Flounce\, n. [Cf. G. flaus, flausch, a tuft of wool or
   hair; akin to vliess, E. fleece; or perh. corrupted fr.
   rounce.]
   An ornamental appendage to the skirt of a woman's dress,
   consisting of a strip gathered and sewed on by its upper edge
   around the skirt, and left hanging.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Flounce \Flounce\, v. t.
   To deck with a flounce or flounces; as, to flounce a
   petticoat or a frock.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Flounce \Flounce\, v. i. [imp. & p. p. Flounced (flounst); p.
   pr. & vb. n. Flouncing.] [Cf. OSw. flunsa to immerge.]
   To throw the limbs and body one way and the other; to spring,
   turn, or twist with sudden effort or violence; to struggle,
   as a horse in mire; to flounder; to throw one's self with a
   jerk or spasm, often as in displeasure.
   [1913 Webster]

         To flutter and flounce will do nothing but batter and
         bruise us.                               --Barrow.
   [1913 Webster]

         With his broad fins and forky tail he laves
         The rising sirge, and flounces in the waves. --Addison.
   [1913 Webster]

WordNet (r) 3.0 (2006):

flounce
    n 1: a strip of pleated material used as a decoration or a trim
         [syn: frill, flounce, ruffle, furbelow]
    2: the act of walking with exaggerated jerky motions
    v 1: walk emphatically

Moby Thesaurus II by Grady Ward, 1.0:

236 Moby Thesaurus words for "flounce":
   amble, antic, barge, bead, beading, bejewel, beribbon, bespangle,
   binding, blunder, bob, bordering, bordure, bounce, bowl along,
   bundle, caper, capriole, caracole, careen, career, carry on,
   cavort, clump, crease, creasing, crimp, crisp, curvet, cut a dido,
   cut capers, cut up, dance, diamond, disport, dog-ear, double,
   double over, doubling, drag, droop, duplicature, edging, enfold,
   engrave, falter, feather, figure, filigree, fimbria, fimbriation,
   flag, flection, flexure, flick, fling, fling off, fling out, flip,
   flirt, flounce out, flounder, flower, flute, fold, fold over,
   fool around, foot, footslog, frill, frilling, fringe, frisk,
   frolic, furbelow, gait, galloon, gallop, gambado, gambol, garland,
   gather, gem, halt, hem, hippety-hop, hitch, hobble, hop,
   horse around, illuminate, infold, interfold, jerk, jewel, jig,
   jigger, jigget, jiggle, jog, joggle, jolt, jump, jump about, labor,
   lap over, lapel, lappet, limp, list, lock step, lumber, lunge,
   lurch, march, mince, mincing steps, motif, ornament, pace, paddle,
   paint, parade, peg, peplum, piaffe, piaffer, pitch,
   pitch and plunge, plait, plat, play, pleat, plica, plicate,
   plication, plicature, plod, pluck, plume, plunge, ply, prance,
   prink, quill, rack, ramp, reel, ribbon, rock, roll, rollick, romp,
   ruche, ruching, ruff, ruffle, sashay, saunter, scuff, scuffle,
   scuttle, seethe, selvage, shamble, shuffle, sidle, single-foot,
   skip, skirting, slink, slither, slog, slouch, slowness, snake,
   snatch, spangle, sport, stagger, stalk, stamp, start, step, stomp,
   storm, straddle, straggle, stride, stroll, strolling gait,
   struggle, strut, stumble, stump, sudden pull, swagger, sway, swing,
   thrash about, tinsel, tittup, toddle, toss, toss and tumble,
   toss and turn, totter, traipse, tread, trimming, trip, trot,
   trudge, tuck, tumble, turn over, tweak, twill, twist, twitch,
   valance, velocity, volutation, waddle, walk, wallop, wallow,
   wamble, welt, welter, wiggle, wobble, wreathe, wrench, yank,
   yerk